Raspberry Pi Compute Module 4 Dual ETH Quad RS485 Base Board (B) (21666)

Raspberry Pi Compute Module 4 - not included in the package!

TheRaspberry Pi Compute Module 4 Dual ETH Quad RS485 Base Board (B) (21666 ) is a base board for the Compute Module 4 Lite/eMMC, suitable for evaluating the Raspberry Pi CM4 Compute Module or for integrating it into end products that require multi-channel RS485 communication or other industrial contexts.

Example of use:

Please note: All third-party devices, cables, and modules in this example are for demonstration purposes only and are not included in the scope of delivery.

Technical specifications:

Interfaces:

1. CM4 connector fits all Compute Module 4 variants
2. IO-VREF. Sets the CM4 IO logic level to 3.3 V (default) or 1.8 V
3. RTC-12C: Selects the 12C bus for RTC. You can select SDA0 and SCLO (default) or GPIO2 and GPIO3
4. RTC INT: select the RTC interrupt pin
- D16: use GPIO16 to receive an interrupt signal during an RTC interrupt (default)
- GL-EN: power down CM4 due to RTC interrupt
- PI-RUN: CM4 will reboot after RTC interrupt
5. SYSTEM: configuration of system functions
- WP-DIS: prevent EEPROM from being overwritten
- BT-DIS: disable Bluetooth function ONLY for CM4 with antenna option
- WIFI-DIS: Disable WiFi function ONLY for CM4 with antenna option
6. Downloading
- ON: CM4 will be booted from the USB-C interface
- OFF: CM4 will boot from an eMMC or Micro SD card
7. PWR & USB
- When the BOOT switch is in the "ON" position, it can be used as a USB port for programming or a DC power supply
- When the BOOT switch is in the "OFF" position, only used as a DC power supply port
8. HDMI0. HDMI port, supports 4K 30fps output
9. USB. 2x USB 2.0 for connecting a variety of USB devices
10. ETHERNET0. CM4 original Gigabit RJ45 ETH
11. ETHERNET1. Extended USB 100M ETH
12. CAM0 and CAM1. 2 MIPI CSI camera ports
13. Sound signal. GPIO22 control
14. FAN. 4-pin connector for cooling fan (supports 5V only) allows speed control via PWM (GPIO18 control, speed measurement not supported)
15. Socket for RTC battery. Supports CR1220 button cell
16. RS485 TX/RX indicator
- TXn: TX indicator for channel n
- RXn: RX indicator for channel n
17. User LED
- USER0: control of GPIO20
- USER1: control of GPIO26
18. PWR. Raspberry Pi power indicator
19. ACT. Indicator of the working status of Raspberry Pi
20. DC 736V. Interface of the DC power supply
21. power supply terminal. DC power supply terminal, supports wide range input voltage (736V)
22. RS485 terminal. 4 isolated RS485 terminals with a distance of 5.08 mm
23. Jumper. Jumper for selecting a 120R balance resistor
24. Selecting the RS485 operating mode
- Full-auto: automatic mode, easy for program control, but the load capacity is weak
- Semi-auto: semi-automatic mode, which requires manual TX/RX switching, with high reliability and large load capacity
25. Encryption chip. ATSHA204 encryption chip provides multiple encryption to ensure data security and reliability
26. Micro SD card slot for connecting a Micro SD card with a pre-recorded image (for the simplified version ONLY)

Overall dimensions: 93.6 mm × 108.8 mm

Information for developers (Wiki): CM4-ETH-RS485-BASE-B

The package includes:

1. CM4-ETH-RS485-BASE-B x1

Weight: 0.100 kg